The Food and Drug Administration (FDA) will now require the rheumatoid arthritis drug Arava (leflunomide) to include information on severe liver injury as part of its black box warning. Arava already carries a boxed warning that its use is contraindicated in pregnant women and women of child-bearing age who are not using a reliable contraception method.
The FDA said its decision was based on a review of 49 adverse event reports -- including 14 cases of fatal liver failure -- between August 2002 and May 2009. The greatest risk for liver injury occurred in patients with pre-existing liver disease and in those who took Arava while taking other drugs known to cause liver injury, according to the FDA. In its safety advisory, the FDA said Arava patients should have their liver enzymes monitored at least monthly for three months after starting the drug and at least quarterly afterwards. Treatment should be stopped if the patient’s ALT rises to greater than two times normal while the patient on leflunomide. A cholestryamine washout should be used to remove the drug from the body.
Patients taking Arava who experience itching, yellow eyes or skin, dark urine, loss of appetite, or light-colored stools should contact their doctor immediately.